Composition for simultaneously laundering and softening fabrics



United States Patent 3,325,404 COMPOSITION FOR SIMULTANEOUSLY LAUN-DERING AND SOFTENING FABRICS Sidney Cohen, Jersey City, N.J., andReginald L. Wakenlan, Philadelphia, Pa., assignors, by mesneassignments, to Millmaster Onyx Corporation, New York, N.Y., acorporation of New York No Drawing. Filed Sept. 19, 1963, Ser. No.310,136 3 Claims. (Cl. 2528.75)

The object of this invention is to provide a composition forsimultaneously laundering and softening fabrics. It is a further objectof this invention to provide composition whereby cationic softeners canbe applied to fabrics at the same time that the goods are beinglaundered with anionic detergents. It is still another object of thisinvention to provide a method whereby the housewife can launder goodswhile, at the same time, applying thereto a cationic softener. It is astill further object of this invention to provide a process by whichtextile fabrics or fibers may be finished with cationic softeners whilesimultaneously applying anionic wetting agents or other anionicsurfactants to the fabric or fibers.

It is well known to the art to apply to laundered goods a quaternaryammonium salt as a cationic softener of the type RG'QR wherein R and Rrepresent alkyl radicals having 14 to 20 carbon atoms, R is a methylradical, R' is a methyl, ethyl or an ethoxylated radical (CH CH O),,Hwhere n is an integer of at least one, and X is a chlorine, bromine,sulfate, methosulfate and ethosulfate anion, by dissolving such asoftener in the final rinse water. Similar materials have also been usedby textile mills as softeners applied in the final rinse. In thepreceding formula, R and R represent an alkyl radical or mixture ofalkyl radicals having from 14 to 20 carbon atoms usually derived fromtallow. Quaternary ammonium compounds of this type are sold insubstantial volume and are used in the application set forth above, moreparticularly in the last rinse in household laundering operations. Theyimpart to the treated goods a pleasant, soft hand and have found muchfavor with housewives.

The preferred alkyl radical, R, in these compounds is usually a mixturecontaining about 60 to 80% of stearyl and about 20 to 40% of cetylradicals and is ordinarily derived from tallow, preferably byhydrogenation or by by hydrogenation of its derivatives used asintermediates in the production of the quaternary ammonium compounds.Softeners of this type being high molecular weight compounds of cationicnature are precipitated by anionic surfactants such as ordinary soaps,alkyl aryl sulfonates, fatty alcohol sulfates, and the like. Theycannot, therefore, be used as such in a detergent solution because theyare precipitated thereby and deposit an insoluble precipitate on thelaundered goods which, rather than having a softening effect, actuallyleaves them as harsh to the feel, or even more so, than as if thesoftener had not been applied.

We have now found the surprising fact that when cationic softeners ofthe foregoing type are combined with a stabilizer, which is a selectedquaternary ammonium compound containing only one alkyl radical havingfrom 8 to 20 carbon atoms in the alkyl chain, hereinafter referred to asmonoalkyl quaternary ammonium salts, they can be dissolved in aqueoussolutions of anionic detergents to yield stable dispersions showinglittle or no tendency to precipitate. Furthermore, when goods arelaundered with such solutions, they are not only 3,325,404 Patented June13, 1967 effectively washed by the anionic detergent, but they are alsosoftened by the cationic softener of the type hereinabove delineated.The monoalkyl quaternary ammonium compound of itself may possess litteor no softening power. The optimum characteristics of good softening andgood compatibility with anionic detergents are exhibited by ratios ofdialkylto monoalkyl quaternary ammonium compounds lying within the rangeof about 1:1 to about 8:1 by weight.

The monoalkyl quaternary ammonium salts which may be used as astabilizer in conjunction with the dialkyl quaternary ammonium softenercompounds previously described conform, in general, to the followingstructure:

wherein R is selected from the group consisting of an alkyl oralkaralkyl radical containing from 8 to 22 carbon atoms, an alkyl benzylphenoxy ethyl radical in which the alkyl radical contains from 8 to 9carbon atoms and in which the phenyl radical may be .substituted by amethyl group; R and R" are selected from the group consisting of methyl,ethyl, propyl, and isopropyl radicals and radicals which, in combinationwith the nitrogen atom of the above formula, form a monocylic,heterocyclic ring system including pyridine, pyrrolidine, andmorpholine; R' is selected from the group consisting of methyl, ethyl,propyl, and i'sopropyl radicals and a benzyl group or substituted benzylgroup including monochlorobenzyl, dichlorobenzyl, methyl benzyl,dimethyl benzyl, ethylbenzyl, diethyl benzyl, isopropyl benzyl, tertiarybutyl benzyl, or another benzyl radical containing from 1 to 4 carbonatoms as a single or as multiple side chains, or R' is the same radicalas R" when R and R" are members of an unsaturated heterocyclic ring inwhich the group, R", is doubly bonded to nitrogen, including pyridine;and X is selected from the group consisting of chloride, bromide,sulfate, methosulfate and ethosulfate ions. Typical examples of thesestabilizer monoalkyl quaternary ammonium compounds are alkyl trimethylammonium chlorides, alkyl benzyl trimethyl ammonium chlorides, lalkyldimethyl benzyl ammonium chlorides, alkyl dimethyl substituted-benzylammonium chlorides wherein the substituted-benzyl radical is methylbenzyl, dimethyl benzyl, ethyl benzyl, and the like, alkyl methylpyrrolidinium chlorides, alkyl ethyl morpholinium chlorides, alkylbenzyl morpholinium chlorides, and the like, as well as correspondingmetho and etho sulfates, in all of which the alkyl group has from 8 to20 carbon atoms. Other monoalkyl quaternary ammonium salts which mayalso be employed include alkyl phenoxy ethyl dimethyl benzyl (and methylbenzyl) ammonium chlorides in which the alkyl radical is isooctyl orisononyl.

It has generally been supposed that surface-active cationic materialsare universally precipitated by surfaceactive anionic materials. Thisis, indeed, the case when dialkyl dimethyl ammonium chloride, dialkyldimethyl ammonium metho sulfate, and dialkyl ethoxylated hydroxy ethylmethyl ammonium chloride solutions are added, alone, to conventionalanionic detergent solutions such as aqueous solutions of soap, alkylbenzene sulfonates, aliphatic hydrocarbon sulfonates, sulfonated oils,sulfonated esters such as sulfonated butyl oleate or sulfonated castoroil, alkyl sulfates, dialkyl esters of alpha sulfo succinic acid, andthe like, which are described in Schwartz, Surface Active Agents, 1949,New York, Interscience Publishers, Inc., pages 25141. We have found thatsuch precipitation is inhibited. or completely prevented when thedialkyl quaternary is combined with the monoalkyl quaternary ammoniumcompounds above enumerated in the proportions hereinabove set forth.

Conventional concentrates of dialkyl quaternary ammonium salts usuallysupplied to formulators for dilution with water to 3 to 6% activeaqueous solutions which are sold in this dilute form to the housewifeusually contain about 75% of dialkyl dimethyl quaternary ammoniumcompound. The balance is water, together with a suitable Water-solubleorganic solvent such as isopropanol. We prefer to prepare approximately75 active concentrates of a blend of dialkyl and monoalkyl quaternarywhich can be readily cut to a 3 to 6% active solution, if desired, thatcan be used by the housewife, laundry, or textile mill by directaddition to the washing solution containing anionic detergent.

In current practice, it is customary for the housewife to add a measuredamount of cationic softener of the dialkyl dimethyl ammonium salt typeto the final rinse water used in a home washing machine so that theamount of softener applied to the fabric by exhaustion from the finalrinse will usually be within the range of 200 to 1000 parts per millionof dry clothes, preferably about 750 parts per million. The process ofthis invention represents a major advance in household launderingprocedures because laundering and softening can both be performed at thesame time. Thus, the housewife preferably adds the softener comprisingboth dialkyl and monoalkyl quaternary salts directly to the soap orother detergent solution and launders and rinses in the conventionalmanner. Similarly, in mill operations, softening can be carried out inthe final scouring operation without interposition of an additionalsoftening step before final drying of the goods.

It should be understood that the concentrated softeners employed in ourinvention may, if desired, contain a water-miscible organic solvent suchas ethanol or isoproanol. P The compatibility of blends of dialkylquaternaries and monoalkyl quaternaries with various anionic surfactantsis illustrated in Table I, using a 0.225% active content of cationic.

figures generally resulted in incompatibility. In all the cases givenabove, however, the minimum compatible anionic/cationic ratios are wellbelow the ratios which would be required for use in home laundering orin textile finishing. Thus, in home laundering, where the use of a 14%active powdered anionic detergent is in the range of 8 ounces per 10pounds of goods, and the softener is used at a concentration ofapproximately 0.07% on the weight of goods, the anionic/cationic ratiorequired in the washing solution would be approximately 10.0, which iswell above the minimum anionic/cationic ratios required for the selectedcompatible anionic/cationic mixtures stated above.

In the practice of this invention, we prefer to use an anionic/ cationicratio, based on the weights of active ingredient of each agent, of 1.5to 20.0. Generally, the higher values of this range of the ratio areutilized in home laundering applications, while the lower values of thisrange are utilized in textile finishing operations.

The method of simultaneously laundering and softening fabrics accordingto this invention is illustrated by the following example.

Example 1 A five-pound load of soiled terry towels was placed in aWestinghouse Commercial Laundromat. Four ounces of Tide, a commerciallyavailable household detergent containing both alkyl aryl sulfonate andsodium alkyl sulfate sold by the Procter & Gamble Company, was added tothe charge and the machine was turned to the Hot position to start theaddition of water. Softener solution was then added through the externalopening provided for addition of liquids, at a level of 750 parts activesoftener per million of towelling. The goods were then laundered in theconventional manner, a single cycle consisting of a wash, three rinses,and a spin. Four complete cycles were performed in each test, detergentand softener both being applied in the same wash bath except in the caseof controls. After the final rinse, the towels were tumble dried andevaluated for cleanliness, yellowing, softness, and absorbency.

TABLE I Ratio of Anionic to Cationic Anionic 1 Cationic by CompatibllityWeight of 100% Active Material 2T2MMS 2 1. 38 Preolpltate.2T2MMS:T2MCl(3:1) 1. 38 Compatible. 2'I2MCl 4 1. 38 Preclpitate.212MClz'12MCl (3:1) 1. 38 Compatible. 2T2MMSzCPC (3:1) 1.3a 1 )o 2T2MC1g. 2?] gleclp'liiiih ornp e. 2T2MMS'T2MC1 (3 1) 0. 40 Precipitate.

0. 40 Compatible. 0. 4.0 Precipitate. do 0. 40 Compatible. 2T2MMSDi-2-ethyl hexyl snliosuccinatm. 1. 10 Preeipitate. 2T2MMS:T2MC1 (3:1) o1.10 Compatible. 2T2MC1 Sodium salt of coconut fatty 1. 3 Preeipitate.

acids. 2T2MMSzT2MCl (3.1)..- --do 1.3 Compatible.

1 Anionic in the form of its sodium salt. 2 2T2MMS is dialkyl dimethylmixture, primarily C -C present in hydrogenated tallow ammoniummethosuliate where the alkyl group is the 3 T2MCl is alkyl dimethylbenzyl ammonium chloride, where the alkyl radical is as defined undernote 2. 4 ZTZMCl is dialkyl dimethyl ammonium chloride, where the alkylgroup is under note 2.

B CPC is eetyl pyridinium chloride.

as defined For comparative purposes, comparable four-cycle launderingsof terry towels were carried out without softener, and anotherfour-cycle laundering was carried out using a softener in the lastrinse, only, of each cycle.

In all cases, cleanliness was excellent. The relative soft- 75 ness ofthe washed goods was evaluated by a panel of methyl benzyl ammoniumchloride, tested as described in Example 1, with the following results:

Softener Ratio of Dialkyl to Softness Rating Monoalkyl Quaternary TABLEII Softener Location softness Discoloration Wicking,

Added Rating 1 in.

4. 8 None 2. 0 1.0 Noticeable yellowing 0.0 5. 8 None 1. 3 1. ONoticeable ye1lowing 0. 0 3. 0 None 1. 3

1 1 shows greatest softness.

A softness rating of 3 or less indicates good softening. Hence, it isapparent that addition of the 3:1 blend of dialkyl quaternary ammoniumsalt and monoalkyl quaternary ammonium salt during the soaping operationgave substantially improved softening over the control wash run withoutsoftener, whereas addition of the dialkyl quaternary ammonium salt,only, during the soaping seriously impaired softness as compared withthe control. Furthermore, the addition of the 3:1 blend during washingresulted in washed goods having no discoloration and exhibiting goodabsorbency, a measure of the utility of the towel in drying operations,as compared with use of the same blend in the last rinse. In the latercase, although softness was somewhat better, the goods were discoloredby the cationic and the wicking was impaired.

Example 2 Another series of tests was run in the same manner as inExample 1 using 3:1 blends of dialkyl dimethyl ammonium metho sulfateand cetyl pyridinium chloride, the same dialkyl quaternary and alkyldimethyl benzyl ammonium chloride, and dialkyl dimethyl ammonium chloride and alkyl dimethyl benzyl ammonium chloride. Table III shows theresults of evaluation.

It is thus apparent that within the range of 85:15 to 60:40 of dialkylquaternary to monoalkyl quaternary,

there is marked softening of the goods when the softener is appliedduring the washing cycle.

It will be apparent that, while We have shown the marked utility of thisinvention in household laundering 0 operations, similar advantagesaccrue to the textile mill degree of water absorbency. The desirablysoft handle imparted to textile fabrics by cationic softeners, which arecationic surfactants of various structures containing one or more longalkyl groups of 16 to 22 carbon atoms, cannot be duplicated by the useof anionic or nonionic types of softening agents. Indeed, the termcationic hand has become a descriptive term in the textile finishingindustry to describe the unique, soft, handle produced by cationicsofteners.

It is apparent from this series of tests that all three combinations ofdialkyl quaternaries and monoalkyl quaternaries gave markedly improvedsoftening over the blank, Whereas the color of the laundered fabric andthe wicking was better, in each case, than when the dialkyl quaternaryalone or the dialkyl quaternary in combination with the monoalkylquaternary was used in the final rinse.

Example 3 In order to determine the effective range of ratios of dialkylquaternary to monoalkyl quaternary when added to the detergent wash,dialkyl dimethyl ammonium metho sulfate was combined in varying amountswith alkyl di- However, treatment of textile materials with efiicientcationic softeners leads to a decrease in the water absorbency of thegoods, making them unattractive for end uses such as towels and diapers.In addition, goods intended for these end uses are usually treated withan anionic wetting agent to confer high absorbency upon them, and thesimultaneous application of cationic softeners with the anionic wettingagent has heretofore been impossible to carry out because of theincompatibility of the cationic softeners with the anionic wettingagent.

As examples of the novel process by which textile materials may now befinished to provide a soft hand and a high absorbency, the followingillustrations are given:

7 Example 4 Unfinished terry cloth (Test Fabrics, Inc.; Style #420) wasthoroughly wet out in water and mangled under sufficient pressure toleave the goods with an 85% pickup of water. The moist terry cloth wasthen treated in a three roll padder with a solution containing thefollowing ingredients, all percentages being given by weight:

Percent 3:1 mixture of 2T2MMS and T2MCl (75% active)- 1.5 Sulfated butyloleate (60% active) 3.0

Water to 100%.

Example 5 46 pounds of 2T2MMS, 9.5 pounds of T2MCl and 19 pounds ofisopropyl alcohol were mixed in a kettle at 50 C. until a uniform blendwas obtained. To this mixture were then added 18. pounds of a 50%solution in isopropyl alcohol of sodium di-(2 ethylhexyl)-sulfosuccinateand 25 pounds of the condensation product of nonyl phenol with 9.5 molesof ethylene oxide. The ingredients were mixed for a short time until auniform blend was obtained.

A 2% by weight aqueous solution of the above blend was prepared and usedto impregnate cotton terry cloth by the same procedure as described inExample 4. The resulting goods had a very soft handle and a wicking testof 1.4 inches.

We claim:

1. A composition for treating fabrics consisting essentially of asurface-active anionic agent and a compatible softening agent, saidsoftening agent consisting essentially of (1) a softener having thestructure:

R C R wherein R and R are alkyls having 14 to 20 carbon atoms, R" ismethyl, R' is a member of the group consisting of methyl and ethyl, andX is a member of the group consisting of chlorine, bromine, sulfate,methosulfate and ethosulfate, and (2) a stabilizer having the structure:

wherein R is a member of the group consisting of alkyl and alkaralkylcontaining 8 to 22 carbon atoms, alkyl benzyl phenoxy ethyl wherein thealkyl has 8 to 9 carbon atoms, and the benzyl is selected from the groupconsisting of unsubstituted and methyl substituted benzyls, R and R" aremembers of the group consisting of methyl, ethyl, propyl, isopropyl, andindividual valences of the hydrocarbon residues of heterocyclic systemsselected from the group consisting of pyridine, pyrrolidine andmorpholine, R is a member of the group consisting of methyl, ethyl,propyl, isopropyl and benzyl, said benzyl being selected from the groupconsisting of unsubstituted and substituted benzyls wherein thesubstituted benzyl is substituted in at least one position by a memberof the group consisting of chlorine, methyl, ethyl, isopropyl, tertiarybutyl and a second benzyl, said second benzyl being substituted in atleast one position by a lower alkyl of 1 to 4 carbon atoms, and X is amember of the group consisting of chloride, bromide, sulfate,methosulfate and ethosulfate, the ratio of softener to stabilizer beingbetween about 1:1 and 8:1 by weight, and the ratio of softening agent toanionic agent being between about 121.5 and 1:20.

2. A process for simultaneously laundering and softening fabrics whichcomprises treating fabrics with an aqueous composition as defined inclaim 1.

3. A composition for simultaneously laundering and softening fabricsconsisting essentially of an anionic surface-active agent and a softenercomposition in the amount by weight of about 1.5 to 1, about 20.0 to 1,respectively, said softener composition consisting essentially ofsoftener agent dialkyl dimethyl ammonium methosulfate wherein the alkylgroup has 14 to 20 carbon atoms derived from hydrogenated tallow and asstabilizer alkyl dimethyl benzyl ammonium chloride wherein the alkylgroup has 14 to 20 carbon atoms derived from hydrogenated tallow, theamount of said softener and stabilizer ranging in the ratio by weightfrom about 85:15 to about 60:40.

References Cited UNITED STATES PATENTS 2,746,928 5/1956 Darragh et a1.252106 3,044,962 7/1962! Brunt et al. 2528.8 X 3,117,113 1/1964 Tudor252875 3,122,502 2/1964 Waldman et al. 252-8.8 3,154,489 10/1964 Du Browet al. 2528.8 X 3,178,366 4/1965 Du Brow et al 2528.8 3,256,180 6/1966Weiss 2528.8

' LEON D. ROSDOL, Primary Examiner.

1. A COMPOSITION FOR TREATING FABRICS CONSISTING ESSENTIALLY OF ASURFACE-ACTIVE ANIONIC AGENT AND A COMPATIBLE SOFTENING AGENT, SAIDSOFTENING AGENT CONSISTING ESSENTIALLY OF (1) A SOFTENER HAVING THESTRUCTURE: